OpenCloudOS-Kernel/Documentation/devicetree/bindings/eeprom/at25.txt

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EEPROMs (SPI) compatible with Atmel at25.
Required properties:
- compatible : Should be "<vendor>,<type>", and generic value "atmel,at25".
Example "<vendor>,<type>" values:
"microchip,25lc040"
"st,m95m02"
"st,m95256"
- reg : chip select number
- spi-max-frequency : max spi frequency to use
- pagesize : size of the eeprom page
- size : total eeprom size in bytes
- address-width : number of address bits (one of 8, 9, 16, or 24).
For 9 bits, the MSB of the address is sent as bit 3 of the instruction
byte, before the address byte.
Optional properties:
- spi-cpha : SPI shifted clock phase, as per spi-bus bindings.
- spi-cpol : SPI inverse clock polarity, as per spi-bus bindings.
- read-only : this parameter-less property disables writes to the eeprom
Obsolete legacy properties can be used in place of "size", "pagesize",
"address-width", and "read-only":
- at25,byte-len : total eeprom size in bytes
- at25,addr-mode : addr-mode flags, as defined in include/linux/spi/eeprom.h
- at25,page-size : size of the eeprom page
Additional compatible properties are also allowed.
Example:
eeprom@0 {
compatible = "st,m95256", "atmel,at25";
reg = <0>
spi-max-frequency = <5000000>;
spi-cpha;
spi-cpol;
pagesize = <64>;
size = <32768>;
address-width = <16>;
};